巢湖流域农田生态系统磷代谢分析

采用物质流分析方法,建立巢湖流域农业种植系统的静态磷代谢分析模型,结合统计数据和文献参数,估算了2008年巢湖流域农田生态系统排水含磷来源分配以及流域各县(市)农田生态系统排水的磷含量.结果表明,巢湖流域整个农田生态系统的排向水体的含磷总量为14125.1158t,其中化肥和还田畜禽粪便是巢湖流域农田生态系统磷输入的主要来源,其排入水体的含磷总量分别为37172.0944t和26230.2336t;而肥西县与合肥市辖区是农田种植对水环境影响最大的区域,其农田生态系统排水含磷总量分别为4077.6575t和2849.133t.     

Environmental Monitoring of Land-Use and Land-Cover Changes in a Mediterranean Region of Turkey

Unprecedented rates of human-induced changes in land use and land cover (LULC) at local and regional scales lead to alterations of global biogeochemical cycles. Driving forces behind LULC changes mainly include rapid growth rates of population and consumption, lack of valuation of ecological services, poverty, ignorance of biophysical limitations, and use of ecologically incompatible technologies. One of the major ecological tragedies of the commons in a Mediterranean region of Turkey is the loss of Lake Amik at the expense of increasing the area of croplands, which used to provide vital ecosystem goods and services for the region. In this study, we aimed at quantifying the effects of past land-use transitions on soil organic carbon (SOC) pools (0–20 cm) in a Mediterranean region of 3930 km², between 1972 and 2000. LULC changes were quantified from a time series of satellite images of Landsat-MSS in 1972, Landsat-5 TM in 1987, and Landsat-7 ETM+ in 2000 using geographic information systems. The study showed that the increase in croplands between 1972 and 1987 took place at the expense of the irreversible losses of Lake Amik and its related wetlands of over 53 km². In the period of 1972 to 2000, croplands, settlements, and evergreen forests increased by 174%, 106%, and 14%, respectively. The increase in settlements occurred mostly to the detriment of croplands. Given the average rates of all the land-use transitions, and associated changes in SOC density for the study region of 3930 km², total SOC pool was estimated to decrease by 14.1% from 130.1 Mt in 1972 to 111.7 Mt in 2000.     

Human impacts on the terrestrial ecosystem of Fildes Peninsula of King George Island, Antarctica

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干旱地区土地利用结构变化与生态服务价值的关系研究——以酒泉市为例

利用酒泉市1997-2006年土地利用变更调查数据和相关统计资料,计算土地利用结构异质性指数和生态服务价值,分析土地利用结构与生态服务价值的变化及其相互关系.结果表明:1997-2006年酒泉市耕地、林地、园地面积在增加,其中耕地增加最多,增加了9 803.15hm2,牧草地、水域和未利用地面积不断减小,其中牧草地减少最多,减少了207 470.56 hm2;酒泉市土地利用结构多样性指数和均匀度增加而优势度降低,土地利用趋于多样化和均匀化;各类土地的生态服务价值都有不同程度的增加,土地利用生态服务价值总体呈增加趋势;土地利用生态服务价值与土地利用结构线性相关,通过增加牧草地、水域和耕地等生态用地面积,提高土地利用集约度,调整土地利用结构促进土地利用的多样化、均匀化,可以增加生态系统稳定性和提高生态系统服务功能的经济价值.     

中国典型脆弱生态区生态系统管理初步研究

我国脆弱生态区分布范围广、类型多,这些地区大都地处偏远,社会环境封闭,生态环境问题突出,开展脆弱生态区的生态系统管理,是脆弱生态区可持续发展的保障。本文系统阐述了我国脆弱生态区的现状及特征、管理的目标与原则、管理的组织实施以及管理手段与措施。     

水生生态系统中的微生物—金属相互作用

阐述了水生生态系统中的微生物—金属相互作用的3种基本形式,即胞内相互作用,胞表相互作用和胞外相互作用;论述了微生物在水生生态系统中有毒金属的迁移和循环模式中所起的重要作用。      

Managing Invasive Aquatic Plants in a Changing System: Strategic Consideration of Ecosystem Services

Abstract:  Climate change is projected to increase stress for many coastal plant communities. Along large portions of the North American coast, habitat degradation from anthropogenic changes to the environment already threaten the community structure of tidal marshes and submerged aquatic grass beds. The potential loss of ecological services historically provided by these communities has been a long-standing rationale for aggressive control of invading plants such as Phragmites australis and Hydrilla verticillata . Increasing evidence of ecological services provided by invasive species such as P. australis and H. verticillata suggest that, in the face of increasing stress, it may be prudent to take a more pragmatic approach regarding the effect of these species on coastal ecosystems. The notable resilience of these species to control efforts and their competitive success and comparative vigor in stressed systems and capacity to provide at least some beneficial services combine to suggest some invasive species may have a useful role in managed coastal ecosystems.     

永定河(北京段)河流生态系统服务价值评估

借鉴《千年生态系统评估》中对生态系统服务的划分（供给、调节、文化与支持四项服务）,建立生态服务价值评价指标体系,开展永定河（北京段）供水、调蓄洪水、气候调节、休闲娱乐、生物多样性等功能的调查研究,明确永定河（北京段）生态系统主要功能与服务.研究结果如下：永定河（北京段）生态服务总价值432.82亿元.其中供给功能价值为...     

云南省生态资产与生态系统生产总值核算体系研究

生态系统作为重要的生态资产,为人类提供生态产品和服务,是人类生存和社会经济可持续发展的基础;生态系统生产总值（GEP）是生态资产提供的生态产品与服务价值总和,是生态资产的重要组成部分,也是生态资产对人类福祉的主要贡献。论文以云南省为例,分析了生态资产和GEP的内涵、关联与核算体系,评价了云南省2010年生态资产状况及其为受益者提供生态产品和服务价值的总和。评价结果显示：云南省2010年生态资产状况总体良好,林地、灌丛和草地生态系统的质量水平属于良等级;农田生态系统的质量水平差;生物多样性质量水平优。云南省2010年GEP总量为29 869.51亿元,其中,直接产品价值为4 132.69亿元,间接服务价值为25 736.81亿元。2010年GEP是当年该省国内生产总值（GDP）的4.13倍。研究结果表明,生态资产与GEP的核算,可以定量反映生态系统状况及其对区域社会经济发展的支撑作用,并为评估区域生态系统保护成效及建立生态系统可持续管理与绩效考核机制提供科学依据。     

成渝经济区生态系统服务功能重要性评价

选取了生物多样性保护重要性、水源涵养重要性和土壤保持重要性3个重要生态系统服务功能进行分析评价,综合评价了成渝经济区生态系统服务功能的重要性及其区域分异规律. 结果表明:成渝经济区极重要区面积为19 244.00 km2>/sup>,占区域总面积的9.25%,主要为生物核心栖息地、极重要水源涵养区以及土壤保持极重要区;重要区面积为46 814.76 km2>/sup>,占区域总面积的22.56%;一般重要区面积为141 344.08 km2>/sup>,占区域总面积的68.19%.